syzbot

REISERFS (device loop0): checking transaction log (loop0)
REISERFS (device loop0): Using r5 hash to sort names
REISERFS (device loop0): using 3.5.x disk format
REISERFS (device loop0): Created .reiserfs_priv - reserved for xattr storage.
======================================================
WARNING: possible circular locking dependency detected
6.4.0-rc2-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor253/5045 is trying to acquire lock:
ffff88807d584090 (&sbi->lock){+.+.}-{3:3}, at: reiserfs_write_lock+0x7a/0xd0 fs/reiserfs/lock.c:27

but task is already holding lock:
ffff888027a7c558 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x1a4/0x600 mm/memory.c:2931

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (sb_pagefaults){.+.+}-{0:0}:
       lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1494 [inline]
       sb_start_pagefault include/linux/fs.h:1598 [inline]
       filemap_page_mkwrite+0x16f/0x640 mm/filemap.c:3566
       do_page_mkwrite+0x1a4/0x600 mm/memory.c:2931
       do_shared_fault mm/memory.c:4595 [inline]
       do_fault mm/memory.c:4663 [inline]
       do_pte_missing mm/memory.c:3647 [inline]
       handle_pte_fault mm/memory.c:4947 [inline]
       __handle_mm_fault mm/memory.c:5089 [inline]
       handle_mm_fault+0x2140/0x5860 mm/memory.c:5243
       do_user_addr_fault arch/x86/mm/fault.c:1440 [inline]
       handle_page_fault arch/x86/mm/fault.c:1534 [inline]
       exc_page_fault+0x7d2/0x910 arch/x86/mm/fault.c:1590
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

-> #1 (&mm->mmap_lock){++++}-{3:3}:
       lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691
       __might_fault+0xba/0x120 mm/memory.c:5732
       reiserfs_ioctl+0x121/0x340 fs/reiserfs/ioctl.c:96
       vfs_ioctl fs/ioctl.c:51 [inline]
       __do_sys_ioctl fs/ioctl.c:870 [inline]
       __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x63/0xcd

-> #0 (&sbi->lock){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3108 [inline]
       check_prevs_add kernel/locking/lockdep.c:3227 [inline]
       validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3842
       __lock_acquire+0x1295/0x2000 kernel/locking/lockdep.c:5074
       lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691
       __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
       __mutex_lock kernel/locking/mutex.c:747 [inline]
       mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
       reiserfs_write_lock+0x7a/0xd0 fs/reiserfs/lock.c:27
       reiserfs_dirty_inode+0xf2/0x240 fs/reiserfs/super.c:704
       __mark_inode_dirty+0x305/0xd90 fs/fs-writeback.c:2424
       generic_update_time fs/inode.c:1859 [inline]
       inode_update_time fs/inode.c:1872 [inline]
       __file_update_time+0x221/0x240 fs/inode.c:2057
       file_update_time+0x350/0x3c0 fs/inode.c:2088
       filemap_page_mkwrite+0x27b/0x640 mm/filemap.c:3567
       do_page_mkwrite+0x1a4/0x600 mm/memory.c:2931
       do_shared_fault mm/memory.c:4595 [inline]
       do_fault mm/memory.c:4663 [inline]
       do_pte_missing mm/memory.c:3647 [inline]
       handle_pte_fault mm/memory.c:4947 [inline]
       __handle_mm_fault mm/memory.c:5089 [inline]
       handle_mm_fault+0x2140/0x5860 mm/memory.c:5243
       do_user_addr_fault arch/x86/mm/fault.c:1440 [inline]
       handle_page_fault arch/x86/mm/fault.c:1534 [inline]
       exc_page_fault+0x7d2/0x910 arch/x86/mm/fault.c:1590
       asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

other info that might help us debug this:

Chain exists of:
  &sbi->lock --> &mm->mmap_lock --> sb_pagefaults

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  rlock(sb_pagefaults);
                               lock(&mm->mmap_lock);
                               lock(sb_pagefaults);
  lock(&sbi->lock);

 *** DEADLOCK ***

2 locks held by syz-executor253/5045:
 #0: ffff88802d301c68 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:142 [inline]
 #0: ffff88802d301c68 (&mm->mmap_lock){++++}-{3:3}, at: do_user_addr_fault arch/x86/mm/fault.c:1391 [inline]
 #0: ffff88802d301c68 (&mm->mmap_lock){++++}-{3:3}, at: handle_page_fault arch/x86/mm/fault.c:1534 [inline]
 #0: ffff88802d301c68 (&mm->mmap_lock){++++}-{3:3}, at: exc_page_fault+0x6a8/0x910 arch/x86/mm/fault.c:1590
 #1: ffff888027a7c558 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x1a4/0x600 mm/memory.c:2931

stack backtrace:
CPU: 0 PID: 5045 Comm: syz-executor253 Not tainted 6.4.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/28/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 check_noncircular+0x2fe/0x3b0 kernel/locking/lockdep.c:2188
 check_prev_add kernel/locking/lockdep.c:3108 [inline]
 check_prevs_add kernel/locking/lockdep.c:3227 [inline]
 validate_chain+0x166b/0x58e0 kernel/locking/lockdep.c:3842
 __lock_acquire+0x1295/0x2000 kernel/locking/lockdep.c:5074
 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5691
 __mutex_lock_common+0x1d8/0x2530 kernel/locking/mutex.c:603
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x1b/0x20 kernel/locking/mutex.c:799
 reiserfs_write_lock+0x7a/0xd0 fs/reiserfs/lock.c:27
 reiserfs_dirty_inode+0xf2/0x240 fs/reiserfs/super.c:704
 __mark_inode_dirty+0x305/0xd90 fs/fs-writeback.c:2424
 generic_update_time fs/inode.c:1859 [inline]
 inode_update_time fs/inode.c:1872 [inline]
 __file_update_time+0x221/0x240 fs/inode.c:2057
 file_update_time+0x350/0x3c0 fs/inode.c:2088
 filemap_page_mkwrite+0x27b/0x640 mm/filemap.c:3567
 do_page_mkwrite+0x1a4/0x600 mm/memory.c:2931
 do_shared_fault mm/memory.c:4595 [inline]
 do_fault mm/memory.c:4663 [inline]
 do_pte_missing mm/memory.c:3647 [inline]
 handle_pte_fault mm/memory.c:4947 [inline]
 __handle_mm_fault mm/memory.c:5089 [inline]
 handle_mm_fault+0x2140/0x5860 mm/memory.c:5243
 do_user_addr_fault arch/x86/mm/fault.c:1440 [inline]
 handle_page_fault arch/x86/mm/fault.c:1534 [inline]
 exc_page_fault+0x7d2/0x910 arch/x86/mm/fault.c:1590
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570
RIP: 0033:0x7f274ace08e6
Code: ee ff ff 90 48 b8 2e 2f 66 69 6c 65 30 00 48 89 04 25 40 00 00 20 e9 91 ee ff ff 66 0f 1f 84 00 00 00 00 00 41 b9 73 00 00 00 <c7> 04 25 c0 00 00 20 2e 2f 62 75 66 44 89 0c 25 c4 00 00 20 e9 58
RSP: 002b:00007f274a4d1210 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 00007f274adb47e8 RCX: 00007f274ad2c989
RDX: 5482b39acbd30459 RSI: 0000000000000000 RDI: 00007f274a4d15e8
RBP: 00007f274adb47e0 R08: 0000000000000000 R09: 0000000000000073
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f274adb47ec
R13: 00007fffdfab0adf R14: 00007f274a4d1300 R15: 0000000000022000
 </TASK>